Motoren svikter.

Because Norwegian usually puts the definite article at the end of the noun.

• en motor = an engine
• motoren = the engine

The ending -en is the definite ending for many masculine/common-gender nouns in Bokmål.

So Motoren svikter literally has the structure The engine fails / is failing.

In Norwegian, the is often built into the noun itself instead of being a separate word in front.

Compare:

• en bil = a car
• bilen = the car
• en motor = an engine
• motoren = the engine

That is why motoren already includes the idea of the.

Svikter is the present tense of the verb svikte.

• å svikte = to fail
• svikter = fails / is failing

Norwegian present tense is often made by adding -r to the infinitive:

• å komme → kommer
• å virke → virker
• å svikte → svikter

It can mean both, depending on context.

Norwegian present tense often covers what English expresses with either:

• simple present: fails
• present progressive: is failing

So Motoren svikter could mean:

• The engine fails
• The engine is failing
• sometimes even The engine is giving out

The exact English translation depends on the situation.

Svikte often suggests that something is not functioning properly, is letting you down, or is beginning to give out. It does not always mean a complete sudden stop, though it can in some contexts.

For example, Motoren svikter may suggest:

• the engine is malfunctioning
• the engine is unreliable
• the engine is starting to give out

This is a bit different from some other verbs:

• stopper = stops
• fungerer ikke = doesn't work
• svikter = fails / is failing / gives out

So svikter can feel a little broader and more nuanced.

No, this is the basic Norwegian sentence pattern:

Subject + verb

• Motoren = subject
• svikter = verb

So:

• Motoren svikter. = The engine is failing.

This is the normal word order for a simple statement.

Yes. Norwegian follows the verb-second rule in main clauses. That means the finite verb usually stays in the second position.

So you get:

• Motoren svikter.
• Nå svikter motoren. = Now the engine is failing.

Notice that when Nå comes first, the verb svikter comes before motoren.

No. Svikte is used much more widely.

It can be used about:

• machines: Motoren svikter.
• body parts or abilities: Hukommelsen svikter. = The memory is failing.
• people or loyalty: Han sviktet vennene sine. = He let his friends down.

So it is a flexible verb. In this sentence, it is simply being used about an engine.

A rough pronunciation guide is:

• Motoren ≈ moh-TOOR-en
• svikter ≈ SVIK-ter

A few notes:

• In motoren, the stress is on the to syllable.
• In svikter, the sv cluster is pronounced together at the start.
• The r sound will depend on dialect.

A rough full pronunciation could be written as:

moh-TOOR-en SVIK-ter

Yes, but it means something different.

• Motoren svikter = The engine is failing
  specific engine

• En motor svikter = An engine fails / is failing
  indefinite, or one engine among others

So the difference is the same basic difference as the engine versus an engine.

Motoren svikter is standard Bokmål.

In Nynorsk, the present tense is often written differently:

• Bokmål: svikter
• Nynorsk: sviktar

So a Nynorsk version would often be:

Motoren sviktar.

The infinitive is å svikte.

• å svikte = to fail
• motoren svikter = the engine fails / is failing

Examples:

• Motoren begynner å svikte. = The engine is starting to fail.
• Det kan svikte. = It can fail.